Question

What are the easiest steps to make a small circuit with an LED flash from a C/C++ program?

I would prefer the least number of dependencies and packages needed.

• What port would I connect something into?
• Which compiler would I use?
• How do I send data to that port?
• Do I need to have a micro-processor? If not I don’t want to use one for this simple project.

EDIT: Interested in any OS specific solutions.

Answer 1

Here’s a tutorial on doing it with a parallel port.

Though I would recommend an Arduino which can be purchased very cheaply and would only involve the following code:

/* Blinking LED  * ------------  *  * turns on and off a light emitting diode(LED) connected to a digital    * pin, in intervals of 2 seconds. Ideally we use pin 13 on the Arduino   * board because it has a resistor attached to it, needing only an LED   *   * Created 1 June 2005  * copyleft 2005 DojoDave <http://www.0j0.org>  * http://arduino.berlios.de  *  * based on an orginal by H. Barragan for the Wiring i/o board  */  int ledPin = 13;                 // LED connected to digital pin 13  void setup() {   pinMode(ledPin, OUTPUT);      // sets the digital pin as output }  void loop() {   digitalWrite(ledPin, HIGH);   // sets the LED on   delay(1000);                  // waits for a second   digitalWrite(ledPin, LOW);    // sets the LED off   delay(1000);                  // waits for a second } 

http://www.arduino.cc/en/Tutorial/BlinkingLED